 <!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>
    var o = {
       x:10,
        y:20
    }


    /**
     *
     * @param ({},{},{})
     * ({})
     */
    o.extend = function(){
       var dest = o;
       var i = 0;
       for(;i<arguments.length;i++){
           for(var j in arguments[i]){
                   dest[j] = arguments[i][j];
           }
       }
    }


    o.extend({
        say:function(){
            console.log(this.x);
        },
        x:20
    });
    o.extend({
        z:10
    },{
        yy:20
    })



</script>
</body>
</html>